Methods for producing a polyol and a polymer dispersed polyol

ABSTRACT

A method for producing a polyoxyalkylene polyol which comprises subjecting propylene oxide and ethylene oxide to ring-opening addition polymerization with an initiator in the presence of a catalyst,  
     wherein the polyoxyalkylene polyol is a polyoxyalkylene polyol obtained by subjecting propylene oxide to ring-opening addition polymerization with an initiator in the presence of a double metal cyanide complex catalyst to form an oxypropylene block chain, subjecting ethylene oxide and propylene oxide to ring-opening addition polymerization randomly to form an oxyalkylene random chain, changing the catalyst and subjecting ethylene oxide to ring-opening addition polymerization in the presence of an alkali metal catalyst to form an oxyethylene block chain,  
     and the polyoxyalkylene polyol is a polyoxyalkylene polyol having a hydroxyl value of from 5 to 56 mgKOH/g, a proportion of an initiator residue of at most 25 mass %, a proportion of the oxypropylene block chain of from 5 to 50 mass %, a total oxyethylene group content of from 5 to 60 mass %, and a ratio of primary hydroxyl groups among terminal hydroxyl groups of at least 60 mol %.

[0001] The present invention relates to methods for producing apolyoxyalkylene polyol and a polymer dispersed polyol. Thepolyoxyalkylene polyol and the polymer dispersed polyol obtained by theproduction methods of the present invention are widely used as amaterial of an elastomer, a synthetic resin, a coating and a sealingmaterial, or as a surfactant, a lubricant, a diluent, a plasticizer,etc. Particularly when they are used as a material for producing aflexible polyurethane foam (hereinafter referred to as flexible foam), aflexible foam having improved mechanical properties such as hardness,moldability, vibrating property and durability can be obtained.

[0002] Heretofore, various studies have been conducted to improveproperties of a flexible foam. For example, in order to improve comfortof a seat cushion of e.g. an automobile to sit on, improvement of e.g.impact resilience, vibrating property and durability has been desired.Further, in recent years, along with a change in taste of users forcomfort to sit on, a flexible foam having a low impact resiliencecoefficient has been desired. With regard to the vibrating property, itis considered to be effective to make decrement in a frequency region towhich human is sensitive (considered to be from 4 to 8 Hz for example,or from 6 to 20 Hz) particularly significant. In order to improve suchproperties, it is considered to be effective to produce a seat cushionby employing a polyoxyalkylene polyol having a higher molecular weight.

[0003] A polyoxyalkylene polyol (hereinafter referred to as polyol) usedas a material of a flexible foam is usually produced by subjecting analkylene oxide such as propylene oxide to ring-open additionpolymerization with e.g. a polyhydric alcohol as an initiator by using asodium type catalyst such as sodium hydroxide or a potassium typecatalyst such as potassium hydroxide. By this production method, amonool having unsaturated bonds (unsaturated monool) is formed as aby-product, and the formation amount of the unsaturated monool increasesalong with decrease in the hydroxyl value (increase in the molecularweight) of the polyol.

[0004] In production of a polyol having a hydroxyl value at a level of56 mgKOH/g which is widely used as a material of a flexible foam, theformation amount of the unsaturated monool is not so large as to be aserious problem. However, in production of a polyol having a highmolecular weight and a low hydroxyl value, the formation amount of theunsaturated monool tends to be problematic. In a case where a flexiblefoam is produced by using a polyol having a high degree of totalunsaturation, problems such as decrease in hardness, deterioration ofpermanent compression set and deterioration of curing property at thetime of molding tend to occur. Further, in a case where a polyol havinga low hydroxyl value is produced by using a sodium type catalyst or apotassium type catalyst, the degree of total unsaturation tends to beremarkably high, and the production is very difficult.

[0005] As a method of producing a polyol having a low degree of totalunsaturation and a low hydroxyl value, a production method of subjectingan alkylene oxide to ring-opening addition polymerization by using adouble metal cyanide complex as a catalyst is proposed in JP-A-2-276821.Although comfort to sit on remarkably improves when a high molecularweight polyol obtained by this production method is used, there may be aproblem in moldability such as air flow, required in addition to comfortto sit on, in some cases. Practically, such a polyol alone is used toproduce a flexible foam, degree of closed-cell tends to be relativelyhigh, thus leading to a defect at the time of crushing treatment in somecases.

[0006] As a method to overcome the problem of moldability, a method forproducing a flexible foam by using as the material a polyol mixturecomprising a polyol produced by using a double metal cyanide complexcatalyst and a polyol produced by using potassium hydroxide is proposedin JP-A-8-231676. However, in this method, as the polyol produced byusing a double metal cyanide complex catalyst, a polyoxyalkylene polyolproduced by subjecting propylene oxide alone to ring-opening additionpolymerization with an initiator and then subjecting ethylene oxidealone to ring-opening addition polymerization, is used, and further, thedegree of unsaturation of the polyol produced by using a potassiumhydroxide catalyst is high, and the degree of unsaturation of the entirepolyol mixture is thereby high, whereby durability of the foam tends tobe insufficient.

[0007] Further, as another method, a method of using a double metalcyanide complex catalyst, subjecting a mixture of ethylene oxide withanother alkylene oxide to ring-opening addition polymerization reactionsystem with an initiator to produce a polyol having a random additionstructure of ethylene oxide with another alkylene oxide in the moleculeof the polyol, and using this polyol to form a flexible foam havingfavorable moldability, is proposed in U.S. Pat. No. 5,605,939 and U.S.Pat. No. 5,648,559. However, the present inventors have tried to producea flexible foam for an automobile seat by using a polyol in Examples asdisclosed in the above patents, but a foam could not be produced asdepressions (collapses) were formed in the inside and on the surface ofthe foam.

[0008] Under these circumstances, the present invention has been made toovercome the above problems, and it is an object of the presentinvention to provide methods for producing a material polyol and apolymer dispersed polyol, which provide, in production of a flexiblefoam using as the material a polyol produced by using a double metalcyanide complex catalyst, a flexible foam having favorable foammoldability maintained, having good physical properties such as hardnessand vibrating property, and having favorable durability particularlyheat and humidity permanent compression set.

[0009] The present invention provides a method for producing apolyoxyalkylene polyol, which comprises subjecting propylene oxide andethylene oxide to ring-opening addition polymerization with an initiatorin the presence of a catalyst, wherein the polyoxyalkylene polyol is apolyoxyalkylene polyol obtained by subjecting propylene oxide toring-opening addition polymerization with an initiator in the presenceof a double metal cyanide complex catalyst to form an oxypropylene blockchain, subjecting ethylene oxide and propylene oxide to ring-openingaddition polymerization randomly to form an oxyalkylene random chain,changing the catalyst and subjecting ethylene oxide to ring-openingaddition polymerization in the presence of an alkali metal catalyst toform an oxyethylene block chain, and the polyoxyalkylene polyol is apolyoxyalkylene polyol having a hydroxyl value of from 5 to 56 mgKOH/g,a proportion of an initiator residue of at most 25 mss %, a proportionof the oxypropylene block chain of from 5 to 50 mass %, a totaloxyethylene group content of from 5 to 60 mass %, and a ratio of primaryhydroxyl groups among terminal hydroxyl groups of at least 60 mol %.

[0010] The present invention further provides a method for producing apolymer dispersed polyol, which comprises polymerizing a monomer havingpolymerizable unsaturated groups employing the polyoxyalkylene polyolobtained by the above production method as a dispersion medium.

[0011] Now, the present invention will be described in detail withreference to the preferred embodiment.

[0012] Structure of Polyol (1)

[0013] The polyoxyalkylene polyol (hereinafter referred to as polyol(1)) of the present invention is a polyoxyalkylene polyol obtained insuch a manner that propylene oxide is subjected to ring-opening additionpolymerization with an initiator in the presence of a double metalcyanide complex catalyst to form an oxypropylene block chain, ethyleneoxide and propylene oxide are subjected to ring-opening additionpolymerization randomly to form an oxyalkylene random chain, then thecatalyst is changed, and ethylene oxide is subjected to ring-openingaddition polymerization in the presence of an alkali metal catalyst toform an oxyethylene block chain.

[0014] Namely, the polyol (1) has an initiator residue (i), anoxypropylene block chain (ii), an oxyalkylene random chain (iii) and anoxyethylene block chain (iv) in its molecule.

[0015] Initiator Residue (i)

[0016] As the initiator for the polyol (1) of the present invention, anactive hydrogen compound such as a polyhydric alcohol, an amine or acondensed type compound may be used. Here, the initiator residue (i) isa moiety in the polyol (1) derived from the initiator. The proportion ofthe initiator residue (i) is preferably at most 25 mass % based on theentire polyol (1), preferably from 2 to 20 mass %.

[0017] Specific examples of the initiator include polyhydric alcoholssuch as ethylene glycol, propylene glycol, 1,4-butanediol, glycerol,trimethylolpropane, pentaerythritol, diglycerol, meso-erythritol, methylglucoside, glucose, sorbitol and sucrose; amines such asethylenediamine, diethylenediamine, triethylenediamine,diaminodiphenylmethane, hexamethylenediamine and propylenediamine; andcondensed type compounds such as phenol resins and novolac resins.

[0018] Such active hydrogen compounds may be used in combination of atleast two. Among these active hydrogen compounds, preferred is apolyhydric alcohol. Particularly, an at least trivalent polyhydricalcohol is preferred in such a viewpoint that hardness of a flexiblefoam employing as the material a polyol produced by using such apolyhydric alcohol as the initiator is likely to be obtained.

[0019] Further, as the initiator, a compound obtained by subjecting analkylene oxide in a small amount to ring-opening addition polymerizationwith the above compound may also be used. The alkylene oxide ispreferably propylene oxide. The molecular weight of the obtainedcompound is preferably at least 650.

[0020] Most preferred as the initiator is a compound having a hydroxylvalue of from 150 to 250 mgKOH/g, obtained by subjecting propylene oxideto ring-opening addition polymerization with an at least trivalentpolyhydric alcohol.

[0021] Oxypropylene Block Chain (ii)

[0022] The polyol (1) of the present invention has an oxypropylene blockchain (ii) formed by using a double metal cyanide complex catalyst,adjacent to the initiator residue (i). The proportion of theoxypropylene block chain (ii) is from 5 to 50 mass % based on the entirepolyol (1), preferably from 10 to 40 mass %. The proportion of theoxypropylene block chain (ii) is particularly preferably from 20 to 30mass %, whereby hardness of the flexible foam can be controlled high. Ifthe oxypropylene block chain exceeds 50 mass %, degree of closed-cell ofthe flexible foam tends to be high, whereby moldability tends todeteriorate, and the curing property tends to deteriorate, wherebyhardness is less likely to be obtained. Further, if the oxypropyleneblock chain (ii) is less than 5 mass %, hardness of the flexible foam isless likely to be obtained.

[0023] Here, in a case where a compound obtained by subjecting propyleneoxide to ring-opening addition polymerization with an at least trivalentpolyhydric alcohol is used as the initiator, the oxypropylene blockchain in the initiator residue (i) and the oxypropylene block chain (ii)formed by using a double metal cyanide complex catalyst can not bedistinguished even when the obtained polyol (1) is analyzed.Accordingly, in a case of verification as the polyol (1), theoxypropylene block chain of the initiator residue (i) and theoxypropylene block chain (ii) formed by using a double metal cyanidecomplex catalyst are not distinguished. Namely, the total proportion ofthe initiator residue (i) and the oxypropylene block chain (ii) ispreferably from 5 to 75 mass %, more preferably from 12 to 60 mass %,based on the entire polyol (1).

[0024] Further, when the polyol (1) wherein the oxypropylene block chain(ii) is adjacent to the initiator residue (i) and another polyol arecompared, the former is preferred, which has favorable moldability.Further, the oxypropylene block chain (ii) is produced by using theabove double metal cyanide complex catalyst, whereas if another catalystis used, an unsaturated monool is produced as a by-product, anddurability of a flexible foam employing the obtained polyol as thematerial tends to deteriorate, such being unfavorable.

[0025] Oxyalkylene Random Chain (iii)

[0026] The polyol (1) of the present invention has an oxyalkylene randomchain (iii) formed by using a double metal cyanide complex catalystadjacent to the oxypropylene block chain (ii). The oxyalkylene randomchain is a structure obtained by supplying ethylene oxide and propyleneoxide in a predetermined proportion to the reaction system, andsubjecting to ring-opening addition polymerization randomly. Theproportion of the oxyalkylene random chain (iii) is preferably from 5 to90 mass % based on the entire polyol (1), preferably from 10 to 80 mass%.

[0027] The content of oxyethylene groups in the oxyalkylene random chain(iii) in the polyol (1) of the present invention is preferably from 3 to35 mass %, more preferably from 5 to 30 mass %, based on the oxyalkylenerandom chain (iii). Namely, the proportion of ethylene oxide topropylene oxide supplied to the reaction system is preferably from 3/97to 35/65, more preferably from 5/95 to 30/70, in a mass ratio (ethyleneoxide/propylene oxide). In a case where the oxyethylene group in theoxyalkylene random chain (iii) is less than this range or exceeds thisrange, degree of closed-cell of the flexible foam tends to be high, andthe moldability may deteriorate in some cases, such being unfavorable.

[0028] Further, when ethylene oxide and propylene oxide are supplied tothe reaction system in a predetermined proportion, the proportion may bechanged during the supplying. By such a method, the content ofoxyethylene groups in the oxyalkylene random chain (iii) can becontrolled in the desired portion of the molecule. For example, in acase where the proportion of ethylene oxide is increased in stages, apolyol (1) wherein the content of oxyethylene groups becomes hightowards the terminal of the molecule of the polyol (1) can be produced.

[0029] Oxyethylene Block Chain (iv)

[0030] The polyol (1) of the present invention has an oxyethylene blockchain (iv) produced by using an alkali metal catalyst adjacent to theoxyalkylene random chain (iii) i.e. at the terminal of the molecule. Thecontent of this oxyethylene block chain (iv) is preferably from 3 to 40mass %, more preferably from 5 to 30 mass %, based on the entire polyol(1). If the oxyethylene block chain (iv) exceeds 40 mass %, shrinkage islikely to occur even after crushing treatment, such being unfavorable.Further, if the oxyethylene block chain (iv) is less than 3 mass %, e.g.collapses of the foam are likely to occur in production of the flexiblefoam, and the production tends to be difficult.

[0031] Composite Metal Cyanide Complex Catalyst

[0032] The polyol (1) of the present invention is obtained by subjectingthe above-described specific alkylene oxides to ring-opening additionpolymerization with an initiator in the presence of the double metalcyanide complex catalyst. As the double metal cyanide complex catalyst,compounds as disclosed in JP-B-46-27250 may, for example, be mentioned.Particularly, a complex containing zinc hexacyanocobaltate as the maincomponent is preferred, and its ether and/or alcohol complexes are morepreferred. By using such a double metal cyanide complex catalyst, theamount of by-product unsaturated monool can be suppressed, anddurability of the flexible foam employing the obtained polyol as thematerial tends to improve.

[0033] Further, the above ether is not particularly limited, but ispreferably a compound of the following formula (hereinafter referred toas compound (X)):

R ¹ —C(CH ₃)₂(OR ⁰)_(n) OH

[0034] wherein R¹ is a methyl group or an ethyl group, R⁰ is an ethylenegroup or a group having a hydrogen atom of an ethylene group substitutedwith a methyl group or an ethyl group, and n is an integer of from 1 to3. R⁰ is particularly preferably a group selected from an ethylenegroup, a propylene group, an ethylethylene group, a 1,2-dimethylethylenegroup and a 1,1-dimethylethylene group.

[0035] As the compound (X), specifically, compounds as disclosed inWO00/02951 may be mentioned. Specifically, the following compounds arepreferred.

[0036] In a case where n is 1, preferred are ethylene glycolmono-tert-butyl ether, propylene glycol mono-tert-butyl ether, ethyleneglycol mono-tert-pentyl ether and propylene glycol mono-tert-pentylether. In a case where n is 2, diethylene glycol mono-tert-butyl etherand diethylene glycol mono-tert-pentyl ether are preferred. In a casewhere n is 3, triethylene glycol mono-tert-butyl ether and triethyleneglycol mono-tert-pentyl ether are preferred. Further, as the compound(X), a compound wherein n is 1 is particularly preferred, and a compoundwherein R¹ is a methyl group is most preferred. Further, as the compound(X), at least two compounds may be used together.

[0037] The above alcohol is not particularly limited and methanol,ethanol, 1-propanol, 2-propanol, 1-butanol, 2-butanol, tert-butylalcohol, pentanol and octanol may, for example, be mentioned, and amongthem, it is preferred to use tert-butyl alcohol.

[0038] In a case where the compound (X) and another compound are usedtogether as organic ligands, the compound to be used together ispreferably one or at least two compounds selected from the groupconsisting of tert-butyl alcohol, 1-butanol, 2-butanol, tert-pentylalcohol, isopentyl alcohol, N,N-dimethylacetoamide, glyme (ethyleneglycol dimethyl ether), diglyme (diethylene glycol dimethyl ether)triglyme (triethylene glycol dimethyl ether), 2-propanol and dioxane.The dioxane may be either 1,4-dioxane or 1,3-dioxane, and 1,4-dioxane ispreferred. As the compound to be used together, tert-butyl alcohol,tert-pentyl alcohol or glyme is particularly preferred, and tert-butylalcohol is most preferred.

[0039] Namely, specific examples of the double metal cyanide complex tobe used in the present invention include a zinchexacyanocobaltate-ethylene glycol mono-tert-butyl ether complex, a zinchexacyanocobaltate-ethylene glycol mono-tert-butyl ether/tert-butylalcohol complex, a zinc hexacyanocobaltate-tert-butyl alcohol complexand a zinc hexacyanocobaltate-glyme complex. Among them, particularlypreferred are a zinc hexacyanocobaltate-ethylene glycol mono-tert-butylether complex and a zinc hexacyanocobaltate-ethylene glycolmono-tert-butyl ether/tert-butyl alcohol complex.

[0040] Alkali Metal Catalyst

[0041] The alkali metal catalyst to be used for formation of theoxypropylene block chain (iv) may be a sodium type catalyst, a potassiumtype catalyst or a cesium type catalyst. The sodium type catalyst may,for example, be a sodium metal, a sodium alkoxide such as sodiummethoxide, sodium hydroxide or sodium carbonate. The same applies to thepotassium type catalyst and the cesium type catalyst.

[0042] In production of the polyol (1) of the present invention, as themethod of changing the double metal cyanide complex catalyst to thealkali metal catalyst, the alkali metal catalyst may be added to thereaction system after the double metal cyanide complex catalyst isdeactivated, or the alkali metal catalyst may be added to the reactionsystem without deactivation. In the latter case, the double metalcyanide complex catalyst is deactivated by addition of the alkali metalcatalyst. As the deactivation method, a treatment by putting water, anacid or an alkali, or a treatment by putting an adsorbent may, forexample, be mentioned.

[0043] Properties of Polyol (1)

[0044] The hydroxyl value of the polyol (1) of the present invention isfrom 5 to 56 mgKOH/g, more preferably from 10 to 42 mgKOH/g. If thehydroxyl value exceeds 56 mgKOH/g and the molecular weight is low,elasticity of the obtained flexible foam tends to be insufficient.Further, if the hydroxyl value is less than 5 mgKOH/g, hardness of theobtained flexible foam is less likely to be obtained.

[0045] The number of hydroxyl groups in the polyol (1) of the presentinvention is preferably from 2 to 8, more preferably from 2.7 to 7, mostpreferably from 2.8 to 5.2. Here, the number of hydroxyl groups is anaverage number of active hydrogen in the initiator. If the number ofhydroxyl groups is less than 2, the obtained flexible foam tends to besoft, and the durability tends to deteriorate. If the number of hydroxylgroups exceeds 8, the obtained flexible foam tends to be hard, andmechanical properties such as elongation tend to deteriorate.

[0046] The degree of unsaturation of the polyol (1) of the presentinvention is preferably at most 0.03 meq/g, more preferably at most0.025 meq/g. If the degree of unsaturation exceeds 0.03 meq/g, i.e. ifthe amount of the unsaturated monool is large, durability and comfort tosit on of the obtained flexible foam tend to deteriorate. As the indexof the durability of the flexible foam, dry heat permanent compressionset and heat and humidity permanent compression set may be mentioned.The higher the degree of unsaturation, the higher the value of thepermanent compression set, and the poorer the durability tends to be.Further, as the index of the comfort to sit on of the flexible foam, theresonance frequency may be mentioned. Such a correlation that as theresonance frequency decreases, transmissibility at 6 Hz at which humanfeels most uncomfortable tends to decrease, and thus the resonancefrequency is suitable as the index.

[0047] The total oxyethylene group content (i.e. the content of alloxyethylene groups contained in the initiator residue (i), oxyalkylenerandom chain (iii) and oxyethylene block chain (iv)) in the polyol (1)of the present invention is from 5 to 60 mass %, more preferably from 10to 40 mass %. Further, the proportion of primary hydroxyl groups amongterminal hydroxyl groups of the polyol, derived from the oxyethyleneblock chain (iv) at the terminal of the molecule of the polyol (1) ofthe present invention, i.e. the ratio of primary hydroxyl groups amongterminal hydroxyl groups is preferably at least 60 mol %, morepreferably from 80 to 95 mol %.

[0048] Polymer Dispersed Polyol

[0049] The present invention further provides a method for producing apolymer dispersed polyol wherein polymer fine particles are stablydispersed in the polyol (1). The polymer dispersed polyol is adispersion system wherein polymer fine particles (dispersoid) are stablydispersed in the base polyol (dispersion medium). Namely, the polymerdispersed polyol of the present invention is a polymer dispersed polyolwherein the above-described polyol (1) is employed as the base polyol.

[0050] The polymer as the polymer fine particles may be an additionpolymerization type polymer or a condensation polymerization typepolymer. The addition polymerization type polymer may be obtained, forexample, by homopolymerizing or copolymerizing a monomer such asacrylonitrile, styrene, a methacrylate ester or an acrylate ester. Thecondensation polymerization type polymer may, for example, be polyester,polyurea, polyurethane or melamine.

[0051] Presence of polymer fine particles in the polyol suppresses thehydroxyl value of the polyol low, and is effective to improve physicalproperties such as hardness and air flow of the flexible foam. Thecontent of the polymer fine particles in the polymer dispersed polyol isnot particularly limited, but is preferably at most 50 mass %, morepreferably from 3 to 40 mass %. In a case where the mass of the polyolis employed for calculation, the mass of the polymer fine particles isnot included.

[0052] Use of Polyol (1)

[0053] The polyol (1) and the polymer dispersed polyol of the presentinvention are widely used as a material of a flexible foam, anelastomer, a synthetic resin, a coating and a sealing material, or as asurfactant, a lubricant, a diluent, a plasticizer, etc. They areparticularly preferably used as a material for producing a flexiblefoam, whereby moldability of the foam, and vibrating property andphysical properties such as hardness of the flexible foam to be obtainedtend to improve. As a method for producing a flexible foam, a method mayusually be mentioned wherein a polyol compound and a polyisocyanatecompound are reacted in the presence of a blowing agent and a catalyst,and in the presence of a foam stabilizer, a crosslinking agent or a cellopener as the case requires.

[0054] As the polyol compound (including a polymer dispersed polyol) tobe reacted in production of the flexible foam, a polyol mixturecontaining the polyol (1) of the present invention and/or the polymerdispersed polyol of the present invention is preferably used. As thepolyol mixture, the polyol (polyol (1) or polymer dispersed polyol) ofthe present invention alone may be used, or another polyol may be usedtogether. The another polyol is not particularly limited so long as itis a polyol used for production of the flexible foam, but is preferablya polyoxyalkylene polyol, preferably a polyoxyalkylene polyol having atotal oxypropylene group content of at least 40 mass %. Among polyols tobe reacted in production of the flexible foam, the content of the polyolof the present invention is preferably at least 20 mass %, morepreferably at least 30 mass %, particularly preferably at least 50 mass%. Further, at least two polyols of the present invention as mixed maybe used. However, the polyol compound (mixture) does not include acrosslinking agent and a cell opener as mentioned hereinafter.

[0055] The hydroxyl value of the polyol mixture is preferably from 5 to56 mgKOH/g, more preferably from 10 to 42 mgKOH/g. Further, the degreeof total unsaturation of the polyol mixture is preferably at most 0.05meq/g, more preferably at most 0.03 meq/g, most preferably at most 0.025meq/g. Further, the average ratio of primary hydroxyl groups amongterminal hydroxyl groups of the polyol mixture is preferably at least 60mol %.

[0056] The polyisocyanate compound is not particularly limited, andaromatic, alicyclic and aliphatic polyisocyanates having at least twoisocyanate groups; a mixture of at least two of the abovepolyisocyanates; and a modified polyisocyanate obtained by modificationthereof may, for example, be mentioned. Specific examples thereofinclude polyisocyanates such as tolylene diisocyanate (TDI),diphenylmethane diisocyanate (MDI), polymethylene polyphenyl isocyanate(common name: crude MDI), xylylene diisocyanate (XDI), isophoronediisocyanate (IPDI) and hexamethylene diisocyanate (HMDI), andprepolymer type modified products, isocyanurate type modified products,urea type modified products and carbodiimide type modified productsthereof. Among them, preferred are TDI, MDI, crude MDI and modifiedproduct thereof.

[0057] The amount of the polyisocyanate compound used is usuallyrepresented by isocyanate index (a value represented by 100 times theproportion of the number of isocyanate groups based on the total numberof active hydrogen of e.g. polyol, crosslinking agent, cell opener andwater). The amount of the polyisocyanate compound used in the presentinvention is preferably from 80 to 120, more preferably from 85 to 110,as represented by the isocyanate index.

[0058] The blowing agent is not particularly limited, but is preferablyat least one member selected from water and inert gases. As the inertgas, the air, nitrogen or carbon dioxide gas may, for example, bementioned. Among them, water is preferred. The amount of the blowingagent is not particularly limited, and in a case where water is used, itis preferably at most 10 parts by mass, more preferably from 0.1 to 8parts by mass, per 100 parts by mass of the polyol compound.

[0059] The above catalyst is not particularly limited so long as it is acatalyst which accelerates a urethanating reaction, and it may, forexample, be a tertiary amine such as triethylenediamine,bis(2-dimethylaminoethyl)ether orN,N,N′,N′-tetramethylhexamethylenediamine; a metal carboxylate such aspotassium acetate or potassium 2-ethylhexanoate; or an organic metalcompound such as dibutyltin dilaurate.

[0060] The foam stabilizer is not particularly limited, and it may, forexample, be a silicone type foam stabilizer or a fluorine type foamstabilizer, and a silicone type foam stabilizer is preferred. By usingsuch a foam stabilizer, homogeneous cell structure can be formed.

[0061] As the crosslinking agent, preferred is a compound having atleast two functional groups having active hydrogen such as a hydroxylgroup, a primary amino group or a secondary amino group. The hydroxylvalue of the crosslinking agent is preferably at least 100 mgKOH/g, morepreferably 150 mgKOH/g, particularly preferably at least 200 mgKOH/g.Further, at least two crosslinking agents may be used together.

[0062] Specific examples thereof include compounds such as ethyleneglycol, propylene glycol, 1,4-butanediol, neopentyl glycol,1,6-hexanediol, diethylene glycol, triethylene glycol, dipropyleneglycol, glycerol, trimethylol propane, pentaerythritol, diglycerol,dextrose, sorbitol, sucrose, monoethanolamine, diethanolamine,triethanolamine, bisphenol A, ethylenediamine, 3,5-diethyl-2,4 (or2,6)-diaminotoluene (DETDA), 2-chloro-p-phenylenediamine (CPA),3,5-bis(methylthio)-2,4 (or 2,6)-diaminotoluene,1-trifluoromethyl-3,5-diaminobenzene,1-trifluoromethyl-4-chloro-3,5-diaminobenzene, 2,4-toluenediamine,2,6-toluenediamine, bis(3,5-dimethyl-4-aminophenyl)methane,4,4′-diaminodiphenylmethane, m-xylylenediamine, 1,4-diaminohexane,1,3-bis(aminomethyl)cyclohexane and isophorone diamine, and compoundsobtained by adding a relatively small amount of an alkylene oxidethereto.

[0063] The cell opener is preferably a polyoxyalkylene polyol having anumber of hydroxyl group of at least 2, a hydroxyl value of from 20 to180 mgKOH/g and an oxyethylene group content exceeding 60 mass %. Byusing such a cell opener, moldability of the flexible foam tends to beimproved, specifically, the crushing load tends to be suppressed low.The amount of the cell opener used is preferably from 0.1 to 5 parts bymass per 100 parts by mass of the polyol compound.

[0064] In production of the flexible foam, in addition to the abovecomponents, a surfactant such as an emulsifying agent or a foamstabilizer; an aging preventing agent such as an antioxidant or aultraviolet ray absorbent; a filler such as calcium carbonate or bariumsulfate; or a known additive or assistant such as a flame retardant, aplasticizer, a colorant or an antifungal agent, may be used as the caserequires.

[0065] As the method of forming a flexible foam, a method of pouring areactive mixture directly into a mold by means of a low pressure foamingmachine or a high pressure foaming machine is preferred. Particularlypreferred is a method of molding in a closed mold (molding method). Inthe present invention, the flexible foam may be produced either by acold curing method or a hot curing method, but a cold curing method ispreferred.

[0066] The flexible foam produced by using as the material the polyol(1) or the polymer dispersed polyol of the present invention, is usefulfor e.g. a cushion, a mattress or a seat. It is particularly suitable asa seat for vehicles such as automobiles.

[0067] Now, the present invention will be described in further detailwith reference to Examples. However, it should be understood that thepresent invention is by no means restricted to such specific Examples.

[0068] Values in foaming formulation in Examples and ComparativeExamples represent parts by mass.

[0069] Examples X1 to X11 are Production Examples of polyoxyalkylenepolyols of the present invention (Examples of the present invention),Examples X12 to X17 are Production Examples of comparativepolyoxyalkylene polyols (Comparative Examples), and Example X18 is aProduction Example of a polyol used as a cell opener.

[0070] Properties of polyols obtained in Production Examples are shownin Table 1. As properties, the following items are shown. The proportion(unit: mass %) of an oxypropylene block chain adjacent to the initiator,(hereinafter referred to as “PO part (1)”) the proportion (unit: mass %)of an oxypropylene block chain not directly connected to the initiator(hereinafter referred to as “PO part (2)”), the proportion (unit: mass%) of an oxyalkylene random chain (hereinafter referred to as “randomportion (1), random portion (2)”), the oxyethylene group content (unit:mass %) at each of the random part (1) and the random part (2)(hereinafter referred to as EO amount), the proportion (unit: mass %) ofthe oxyethylene block chain at the terminal (hereinafter referred to as“EO part”), the hydroxyl value (unit: mgKOH/g), the ratio of primaryhydroxyl groups among terminal hydroxyl groups (unit: mol %) and thedegree of unsaturation (unit: meq/g).

[0071] The hydroxyl value and the degree of unsaturation were measuredby a method in accordance with JIS K-1557. In Production Examples, aDMC-METB complex catalyst is meant for a zinchexacyanocobaltate-ethylene glycol mono-tert-butyl ether complexcatalyst, a DMC-METB/TBA complex catalyst is meant for a zinchexacyanocobaltate-ethylene glycol mono-tert-butyl ether/tert-butylalcohol complex catalyst, a DMC-TBA complex catalyst is meant for a zinchexacyanocobaltate-tert-butyl alcohol complex catalyst, and a DMC-glymecomplex catalyst is meant for a zinc hexacyanocobaltate-glyme complexcatalyst.

[0072] The initiator 1 is a compound having a hydroxyl value of 168mgKOH/g obtained by adding propylene oxide to glycerol, and theinitiator 2 is a compound having a hydroxyl value of 234 mgKOH/gobtained by adding propylene oxide to glycerol.

POLYOL PRODUCTION EXAMPLES EXAMPLE X1

[0073] Production of Polyol A1

[0074] 1,525 g of propylene oxide was subjected to a reaction by using aDMC-METB complex catalyst in the presence of 1,000 g of the initiator 1at about 120° C., and then 2,833 g of an ethylene oxide/propylene oxidemixture containing 11.6 mass % of ethylene oxide was reacted therewithat about 120° C. Then, potassium hydroxide was added to the reactionsystem to change the catalyst to potassium hydroxide, and using thispotassium hydroxide catalyst, 1,097 g of ethylene oxide was reactedtherewith at about 120° C., and the production was completed. After thereaction, a treatment with an adsorbent (synthetic magnesium silicate)and filtration were carried out to obtain polyol A1 having a hydroxylvalue of 27.3 mgKOH/g.

EXAMPLE X2

[0075] Production of Polyol A2

[0076] Polyol A2 having a hydroxyl value of 27.8 mgKOH/g was obtained inthe same manner as in the production of polyol A1 except that 2,833 g ofan ethylene oxide/propylene oxide mixture having an ethylene oxidecontent of 23.2 mass % was used.

EXAMPLE X3

[0077] Production of Polyol B1

[0078] 2,279 g of propylene oxide was subjected to a reaction by using aDMC-METB complex catalyst in the presence of 1,000 g of the initiator 1at about 120° C., and then 2,278 g of an ethylene oxide/propylene oxidemixture containing 14.4 mass % of ethylene oxide was reacted therewithat about 120° C., then 905 g of ethylene oxide was reacted by using asodium methoxide catalyst at about 120° C., and the production wascompleted. After the reaction, a treatment with an adsorbent (syntheticmagnesium silicate) and filtration were carried out to obtain polyol B1having a hydroxyl value of 27.6 mgKOH/g.

EXAMPLE X4

[0079] Production of Polyol B2

[0080] Polyol B2 having a hydroxyl value of 27.8 mgKOH/g was obtained inthe same manner as in the production of polyol B1 except that aDMC-METB/TBA complex catalyst was used instead of the DMC-METB complexcatalyst.

EXAMPLE X5

[0081] Production of Polyol B3

[0082] Polyol B3 having a hydroxyl value of 27.7 mgKOH/g was obtained inthe same manner as in the production of polyol B1 except that aDMC-glyme complex catalyst was used instead of the DMC-METB complexcatalyst.

EXAMPLE X6

[0083] Production of Polyol C

[0084] 2,473 g of propylene oxide was subjected to a reaction by using aDMC-METB complex catalyst in the presence of 1,000 g of the initiator 1at about 120° C., and then 2,174 g of an ethylene oxide/propylene oxidemixture containing 14.4 mass % of ethylene oxide was reacted therewithat about 120° C., then 627 g of ethylene oxide was reacted therewith byusing a sodium methoxide catalyst at about 120° C., and the productionwas completed. After the reaction, a treatment with an adsorbent(synthetic magnesium silicate) and filtration were carried out to obtainpolyol C having a hydroxyl value of 28.1 mgKOH/g.

EXAMPLE X7

[0085] Production of Polyol D

[0086] 3,137 g of propylene oxide was subjected to a reaction by using aDMC-METB complex catalyst in the presence of 1,000 g of the initiator 1at about 120° C., and then 1,259 g of an ethylene oxide/propylene oxidemixture containing 14.4 mass % of ethylene oxide was reacted therewithat about 120° C., then 878 g of ethylene oxide was reacted therewith byusing a potassium hydroxide catalyst at about 120° C., and theproduction was completed. After the reaction, a treatment with anadsorbent (synthetic magnesium silicate) and filtration were carried outto obtain polyol D having a hydroxyl value of 28.3 mgKOH/g.

EXAMPLE X8

[0087] Production of Polyol E

[0088] 630 g of propylene oxide was subjected to a reaction by using aDMC-METB complex catalyst in the presence of 1,000 g of the initiator 1at about 120° C., and then 4,014 g of an ethylene oxide/propylene oxidemixture containing 11 mass % of ethylene oxide was reacted therewith atabout 120° C., then 691 g of ethylene oxide was reacted therewith byusing a potassium hydroxide catalyst at about 120° C., and theproduction was completed. After the reaction, a treatment with anadsorbent (synthetic magnesium silicate) and filtration were carried outto obtain polyol E having a hydroxyl value of 27.8 mgKOH/g.

EXAMPLE X9

[0089] Production of Polyol F1

[0090] 2,833 g of an ethylene oxide/propylene oxide mixture containing11.6 mass % of ethylene oxide was subjected to a reaction by using aDMC-METB complex catalyst in the presence of 1,000 g of the initiator 1at about 120° C., and then 1,525 g of propylene oxide was reactedtherewith at about 120° C., then 1,097 g of ethylene oxide was reactedtherewith by using a potassium hydroxide catalyst at about 120° C., andthe production was completed. After the reaction, a treatment with anadsorbent (synthetic magnesium silicate) and filtration were carried outto obtain polyol F1 having a hydroxyl value of 27.9 mgKOH/g.

EXAMPLE X10

[0091] Production of Polyol F2

[0092] Polyol F2 having a hydroxyl value of 26.9 mgKOH/g was obtained inthe same manner as in the production of polyol F1 except that 2,833 g ofan ethylene oxide/propylene oxide mixture having an ethylene oxidecontent of 23.2 mass % was used.

EXAMPLE X11

[0093] Production of Polyol G

[0094] 3,817 g of propylene oxide was subjected to a reaction by using aDMC-METB complex catalyst in the presence of 1,000 g of the initiator 1at about 120° C., and then 591 g of an ethylene oxide/propylene oxidemixture containing 21.4 mass % of ethylene oxide was reacted therewithat about 120° C., then 953 g of ethylene oxide was reacted therewith byusing a potassium hydroxide catalyst at about 120° C., and theproduction was completed. After the reaction, a treatment with anadsorbent (synthetic magnesium silicate) and filtration were carried outto obtain polyol G having a hydroxyl value of 28.1 mgKOH/g.

EXAMPLE X12

[0095] Production of Polyol H

[0096] 253 g of propylene oxide was subjected to a reaction by using aDMC-METB complex catalyst in the presence of 1,000 g of the initiator 1at about 120° C., and then 4,387 g of an ethylene oxide/propylene oxidemixture containing 11 mass % of ethylene oxide was reacted therewith atabout 120° C., then 695 g of ethylene oxide was reacted therewith byusing a potassium hydroxide catalyst at about 120° C., and theproduction was completed. After the reaction, a treatment with anadsorbent (synthetic magnesium silicate) and filtration were carried outto obtain polyol H having a hydroxyl value of 27.9 mgKOH/g.

EXAMPLE X13

[0097] Production of Polyol J

[0098] 252 g of propylene oxide was subjected to a reaction by using aDMC-TBA complex catalyst in the presence of 720 g of the initiator 2 atabout 120° C., and then 4,487 g of an ethylene oxide/propylene oxidemixture containing 13 mass % of ethylene oxide was reacted therewith atabout 120° C., then 813 g of an ethylene oxide/propylene oxide mixturecontaining 40 mass % of ethylene oxide was reacted therewith at about120° C., and the production was completed. After the reaction, atreatment with an adsorbent (synthetic magnesium silicate) andfiltration were carried out to obtain polyol J having a hydroxyl valueof 27.9 mgKOH/g.

EXAMPLE X14

[0099] Production of Polyol K

[0100] 5,550 g of propylene oxide was subjected to a reaction by using aDMC-METB complex catalyst in the presence of 1,000 g of the initiator 1at about 120° C., and then 1,103 g of an ethylene oxide was reactedtherewith by using a potassium hydroxide catalyst at about 120° C., andthe production was completed. After the reaction, a treatment with anadsorbent (synthetic magnesium silicate) and filtration were carried outto obtain polyol K having a hydroxyl value of 23.9 mgKOH/g.

EXAMPLE X15

[0101] Production of Polyol L1

[0102] 6,467 g of propylene oxide was subjected to a reaction by using apotassium hydroxide catalyst in the presence of 1,000 g of the initiator1 at about 110° C., and then 1,423 g of ethylene oxide was reactedtherewith at about 110° C., and the production was completed. After thereaction, a treatment with an adsorbent (synthetic magnesium silicate)and filtration were carried out to obtain polyol L1 having a hydroxylvalue of 24 mgKOH/g.

EXAMPLE X16

[0103] Production of Polyol L2

[0104] 5,378 g of propylene oxide was subjected to a reaction by using apotassium hydroxide catalyst in the presence of 1,000 g of the initiator1 at about 110° C., and then 1,257 g of ethylene oxide was reactedtherewith at about 110° C., and the production was completed. After thereaction, a treatment with an adsorbent (synthetic magnesium silicate)and filtration were carried out to obtain polyol L2 having a hydroxylvalue of 27.9 mgKOH/g.

EXAMPLE X17

[0105] Production of Polyol L3

[0106] 4,416 g of propylene oxide was subjected to a reaction by using apotassium hydroxide catalyst in the presence of 1,000 g of the initiator1 at about 110° C., and then 904 g of ethylene oxide was reactedtherewith at about 110° C., and the production was completed. After thereaction, a treatment with an adsorbent (synthetic magnesium silicate)and filtration were carried out to obtain polyol L3 having a hydroxylvalue of 35.5 mgKOH/g.

EXAMPLE X18

[0107] Production of Polyol T

[0108] 5,000 g of an ethylene oxide/propylene oxide mixture containing80 mass % of ethylene oxide was subjected to a reaction by using apotassium hydroxide catalyst in the presence of 1,000 g of the initiator1 at about 120° C., and the production was completed. After thereaction, a treatment with an adsorbent (synthetic magnesium silicate)and filtration were carried out to obtain polyol T having a hydroxylvalue of 27.9 mgKOH/g. TABLE 1 PO part Random part Random part PO partEO Ratio of (1) (1) (2) (2) part hydroxyl groups Pro- Pro- EO Pro- EOPro- Pro- Hydroxyl being primary Degree of Polyol portion portion amountportion amount portion portion value hydroxyl groups unsaturation A123.6 43.9 11.6 — — — 17 27.3 87 0.016 F1 — 43.9 11.6 — — 23.6 17 27.9 870.014 A2 23.6 43.9 23.2 — — — 17 27.8 87 0.012 F2 — 43.9 23.2 — — 23.617 26.9 87 0.010 B1 35.3 35.3 14.4 — — — 14 27.6 86 0.016 B2 35.3 35.314.4 — — — 14 27.8 86 0.009 B3 35.3 35.3 14.4 — — — 14 27.7 86 0.018 C39.4 34.7 14.4 — — — 10 28.1 83 0.015 D 50.0 20.0 14.4 — — — 14 28.3 870.014 E 9.9 63.4 11 — — — 11 27.8 83 0.016 G 60 9.3 21.4 — — — 15 28.186 0.019 H 4.0 69.3 11 — — — 11 27.9 83 0.011 J 4.0 71.5 13 13.0 40 — —27.9 19 0.010 K 72.5 — — — — — 14.4 23.9 87 0.020 L1 72.7 — — — — — 1624 87 0.085 L2 70.4 — — — — — 16.5 27.9 87 0.065 L3 69.9 — — — — — 14.335.5 75 0.060

[0109] TABLE 2 Crosslinking Propylene oxide/ethylene oxide additionagent a1 product of sorbitol, hydroxyl value: 450 mgKOH/g CrosslinkingDiethanolamine agent a2 Catalyst b1 Dipropylene glycol (DPG) solution oftriethylenediamine (TEDA L-33, tradename, manufactured by TOSOHCORPORATION) Catalyst b2 DPG solution of bis-[(2-dimethylamino)ethyl]ether (TOYOCAT ET, tradename, manufactured by TOSOHCORPORATION) Foam Silicone foam stabilizer (SRX-274C, stabilizer ctradename, manufactured by TORAY SILICONE) Cell opener Polyol T Blowingagent Water Polyol N Polymer dispersed polyol whereinacrylonitrile/styrene copolymer particles (20 mass %) are dispersed inpolyol A1 (80 mass %) as a dispersion medium Polyol P Polymer dispersedpolyol wherein acrylonitrile/styrene copolymer particles (20 mass %) aredispersed in polyol C (80 mass %) as a dispersion medium Polyol QPolymer dispersed polyol wherein acrylonitrile/styrene copolymerparticles (20 mass %) are dispersed in polyol K (80 mass %) as adispersion medium Polyol R Polymer dispersed polyol whereinacrylonitrile/styrene copolymer particles (20 mass %) are dispersed inpolyol L2 (80 mass %) as a dispersion medium Polyol S Polymer dispersedpolyol wherein acrylonitrile/styrene copolymer particles (22 mass %) aredispersed in polyol L3 (78 mass %) as a dispersion medium PolyisocyanateMixture of TDI-80 (mixture of 2,4- TDI/2,6-TDI = 80/20 mass %)/crude MDI= 80/20 mass %, isocyanate group content: 44.8 mass % (Coronate 1021,tradename, manufactured by NIPPON POLYURETHANE INDUSTRY CO., LTD.)

[0110] A flexible polyurethane foam was produced by using materialsshown in Table 2 in an amount shown in Table 3 or 4. A mixture of allthe materials except for polyisocyanate (polyol system) and apolyisocyanate compound were respectively adjusted to have a liquidtemperature of 25±1° C., the polyisocyanate compound was added to thepolyol system, followed by mixing with stirring by a high-speed mixerfor 5 seconds, and the mixture was immediately poured and closed in analuminum mold in a size of 400 mm lengthwise and breadthwise and 100 mmin height, heated to 60° C. After curing for 6 minutes, a polyurethanefoam was taken out and left to stand for at least 24 hours, and thenvarious physical properties were measured. The results are shown inTables 3 and 4.

[0111] The crushing property was evaluated as the characteristics of themoldability. The crushing property was evaluated by productivity whenthe foam was compressed up to 25% of the thickness of the foam and thefoam cells were released, immediately after the foam was taken out fromthe mold (400 mm×400 mm×100 mm), and evaluated in accordance with suchevaluation standards that ◯: good, Δ: rather poor. Further, the loadapplied to the surface of 400 mm×400 mm at the time of compression wasevaluated as the crushing load (unit: N). Here, the measurement methodsof the foam physical properties were in accordance with the followingmethods, and with regard to the core density, one cut into a size of 100mm lengthwise and breadthwise and 50 mm in height, having the skinportion removed from the center portion of the foam, was used formeasurement.

[0112] With regard to the resonance frequency, there is a correlationbetween the molded foam for test piece having a size of 400 mm×400mm×100 mm and an actual molded foam for a seat cushion, and the actualmolded foam tends to have a resonance frequency higher than that of thetest piece by from about 0.2 to about 1 Hz, depending upon e.g. thethickness and shape in general.

[0113] The degree of unsaturation in Tables 3 and 4 is the degree oftotal unsaturation (unit: meq/g) of the polyol or the base polyol in thepolymer dispersed polyol.

[0114] Now, standards used for measurement of the physical properties ofthe flexible foam are shown below.

[0115] Overall density (unit: kg/m³), core density (unit: kg/m³),25%-ILD hardness (unit: N/314 cm²), core impact resilience coefficient(unit: %), tear strength (N/cm), tensile strength (kPa), elongation (%),dry heat permanent compression set (unit: %) and heat and humiditypermanent compression set (unit: %) were measured by methods inaccordance with JIS K6400. Hysteresis loss (unit: %) was measured by amethod in accordance with JASO B407-87. Resonance frequency (unit: Hz)and transmissibility at 6 Hz were measured by methods in accordance withJASO B407-87 (excitation amplitude: ±2.5 mm, pressing plate: ironabrasive plate, load: 490 N). TABLE 3 Examples 1 2 3 4 5 6 7 8 9 PolyolA1:60 A2:60 B1:60 B2:60 B3:60 C:60 L2:60 D:70 E:60 R:40 N:20 R:40 R:40R:40 R:40 N:40 N:30 P:20 R:20 R:20 Degree of total unsaturation (meq/g)0.033 0.023 0.033 0.028 0.034 0.032 0.048 0.015 0.024 Crosslinking agenta1 3.0 3.0 3.0 3.0 3.0 3.0 3.0 3.0 3.0 Crosslinking agent a2 1.0 1.0 1.01.0 1.0 1.0 1.0 1.0 1.0 Catalyst b1 0.5 0.5 0.5 0.5 0.5 0.5 0.5 0.5 0.5Catalyst b2 0.12 0.12 0.12 0.12 0.12 0.12 0.12 0.12 0.12 Foam stabilizerc 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 Blowing agent 3.0 3.0 3.0 3.0 3.03.0 3.0 3.0 3.0 Isocyanate index 105 105 105 105 105 105 105 105 105Moldability ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ Overall density (kg/m³) 48.1 47.3 48.748.3 48.7 48.9 48.5 48.3 48.7 Core density (kg/m³) 42.5 41.2 42.6 42.342.6 42.7 42.8 42.5 42.5 25%-ILD hardness (N/314 cm²) 246 214 206 202198 205 225 210 211 Core impact resilience coefficient (%) 63 62 64 6464 66 63 62 63 Tear strength (N/cm) 6.4 6.2 6.5 6.2 6.0 6.2 6.4 6.5 6.2Tensile strength (kPa) 140 138 145 137 133 140 145 146 139 Elongation(%) 103 105 102 106 102 105 105 96 104 Dry heat permanent compressionset (%) 3.8 4.5 3.1 2.9 4.6 4.6 4.3 4.5 4.4 Heat and humidity permanentcompression set (%) 12.0 12.5 11.3 10.9 12.8 12.5 12.8 12.8 12.3Hysteresis loss (%) 19.4 20.4 18.9 18.7 21.0 18.4 20.0 19.6 18.5Resonance frequency (Hz) 3.35 3.55 3.40 3.38 3.60 3.50 3.59 3.55 3.50Transmissibility at 6 Hz 0.69 0.75 0.73 0.70 0.78 0.75 0.77 0.78 0.73Crushing load (N) 960 980 686 588 1176 451 637 1019 637

[0116] TABLE 4 Examples 10 11 12 13 14 15 16 17 18 Polyol A1:60 D:70F1:60 K:20 L1:60 G:60 H:60 J:60 F2:60 R:40 N:30 R:40 L2:50 R:40 R:40R:40 S:40 R:40 Q:30 Degree of total unsaturation (meq/g) 0.033 0.0150.032 0.044 0.078 0.035 0.030 0.027 0.029 Crosslinking agent a1 3.0 3.03.0 3.0 3.0 3.0 3.0 3.0 3.0 Crosslinking agent a2 1.0 1.0 1.0 1.0 1.01.0 1.0 1.0 1.0 Catalyst b1 0.5 0.5 0.5 0.5 0.5 0.5 0.5 0.5 0.5 Catalystb2 0.12 0.12 0.12 0.12 0.12 0.12 0.12 0.12 0.12 Foam stabilizer c 1.01.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 Cell opener 1.0 3.0 — — — — — — —Blowing agent 3.0 3.0 3.0 3.0 3.0 3.0 3.0 3.0 3.0 Isocyanate index 105105 105 105 105 105 105 105 105 Moldability ◯ ◯ Puncture Δ ◯ Δ ◯Collapses Puncture Overall density (kg/m³) 48.4 48.6 48.9 48.2 48.8 47.9Core density (kg/m³) 42.8 42.7 42.6 43.7 42.1 41.8 25%-ILD hardness(N/314 cm²) 238 220 213 176 160 159 Core impact resilience coefficient(%) 65 64 69 67 63 65 Tear strength (N/cm) 6.0 6.3 6.1 6.2 6.0 5.18Tensile strength (kPa) 135 141 146 135 127 120 Elongation (%) 107 104110 107 100 100 Dry heat permanent compression set (%) 3.1 2.9 5.1 7.95.1 4.3 Heat and humidity permanent compression set (%) 10.3 9.8 14.518.6 15.5 14.8 Hysteresis loss (%) 17.0 17.5 18.8 23.0 21.6 20.8Resonance frequency (Hz) 3.30 3.40 3.60 4.85 3.70 3.65 Transmissibilityat 6 Hz 0.65 0.65 0.88 0.98 0.90 0.88 Crushing load (N) 588 735 1470 2351313 392

[0117] Examples 1 to 11 in Tables 3 and 4 are Examples of the presentinvention. As the polyol (1) produced in such a manner that propyleneoxide is subjected to a reaction continuously in an amount of from 5 to50 mass % adjacent to the initiator by using the double metal cyanidecomplex catalyst, ethylene oxide and propylene oxide are randomlyreacted therewith, and then ethylene oxide is reacted therewith by usingan alkali metal catalyst, is used as the material, a foam havingfavorable moldability, favorable physical properties such as hardnessand vibrating property, and favorable durability particularly heat andhumid permanent compression set can be obtained. Particularly inExamples 10 and 11, as the polyol T is used as the cell opener, thecrushing load can be suppressed low, and favorable moldability isobtained.

[0118] Examples 12 to 18 in Table 4 are Comparative Examples.

[0119] In Examples 12 and 18, puncture was formed on the foam at thetime of crushing treatment, whereby physical properties could not bemeasured.

[0120] In Examples 13, in order to make up for failure in moldabilitycaused by the polyol K used as the material produced by using the doublemetal cyanide complex catalyst not having an oxyalkylene random chain,the polyol L2 synthesized by using a potassium hydroxide catalyst ismixed and used as the material, whereby the degree of total unsaturationof the polyol is high, and the durability is insufficient. Further, themoldability is not sufficient.

[0121] In Example 14, the polyol produced with a potassium hydroxidecatalyst is used, whereby the durability is poor.

[0122] In Example 15, a polyol wherein the oxypropylene block chainadjacent to the initiator is 60 mass % based on the entire polyol isused, whereby the reactivity with the polyisocyanate is insufficient,and the hardness is low.

[0123] In Example 16, a polyol wherein the oxypropylene block chainadjacent to the initiator is 4 mass % based on the entire polyol isused, whereby the hardness is insufficient.

[0124] In Example 17, at the terminal of the polyol L produced by usingthe double metal cyanide complex catalyst, production was not terminatedwith the reaction of ethylene oxide, whereby collapses were generatedand a foam could not be formed, and physical properties could not bemeasured.

[0125] By employing a polyol having a specific structure of the presentinvention, a flexible polyurethane foam having improved moldability, andfavorable physical properties such as hardness and vibrating propertycan be obtained. Further, the polyol (1) of the present invention isproduced by using a double metal cyanide complex catalyst, wherebyphysical properties such as durability particularly heat and humiditypermanent compression set are also excellent.

[0126] The entire disclosure of Japanese Patent Application No.2001-218348 filed on Jul. 18, 2001 and Japanese Patent Application No.2002-32839 filed on Feb. 8, 2002 including specification, claims andsummary are incorporated herein by reference in its entirety.

What is claimed is:
 1. A method for producing a polyoxyalkylene polyolwhich comprises subjecting propylene oxide and ethylene oxide toring-opening addition polymerization with an initiator in the presenceof a catalyst, wherein the polyoxyalkylene polyol is a polyoxyalkylenepolyol obtained by subjecting propylene oxide to ring-opening additionpolymerization with an initiator in the presence of a double metalcyanide complex catalyst to form an oxypropylene block chain, subjectingethylene oxide and propylene oxide to ring-opening additionpolymerization randomly to form an oxyalkylene random chain, changingthe catalyst and subjecting ethylene oxide to ring-opening additionpolymerization in the presence of an alkali metal catalyst to form anoxyethylene block chain, and the polyoxyalkylene polyol is apolyoxyalkylene polyol having a hydroxyl value of from 5 to 56 mgKOH/g,a proportion of an initiator residue of at most 25 mass %, a proportionof the oxypropylene block chain of from 5 to 50 mass %, a totaloxyethylene group content of from 5 to 60 mass %, and a ratio of primaryhydroxyl groups among terminal hydroxyl groups of at least 60 mol %. 2.The method for producing a polyoxyalkylene polyol according to claim 1,wherein in the formation of the oxyalkylene random chain, the proportionof ethylene oxide to propylene oxide to be subjected to the ring-openingaddition polymerization is within a range of from 3/97 to 35/65 in amass ratio.
 3. The method for producing a polyoxyalkylene polyolaccording to claim 1, wherein the proportion of the oxyethylene blockchain in the polyoxyalkylene polyol is from 3 to 40 mass %.
 4. Themethod for producing a polyoxyalkylene polyol according to claim 1,wherein the proportion of the oxyalkylene random chain in thepolyoxyalkylene polyol is from 5 to 90 mass %.
 5. The method forproducing a polyoxyalkylene polyol according to claim 1, wherein thedouble metal cyanide complex catalyst has a compound of the followingformula as at least part of organic ligands: R ¹ —C(CH ₃)₂(OR ⁰)_(n) OHwherein R¹ is a methyl group or an ethyl group, R⁰ is an ethylene groupor a group having a hydrogen atom of an ethylene group substituted witha methyl group or an ethyl group, and n is an integer of from 1 to
 3. 6.A method for producing a polymer dispersed polyol, which comprisespolymerizing a monomer having polymerizable unsaturated groups byemploying a polyoxyalkylene polyol as a dispersion medium, wherein thepolyoxyalkylene polyol is one obtained by subjecting propylene oxide andethylene oxide to ring-opening addition polymerization with an initiatorin the presence of a catalyst; is a polyoxyalkylene polyol obtained bysubjecting propylene oxide to ring-opening addition polymerization withan initiator in the presence of a double metal cyanide complex catalystto form an oxypropylene block chain, subjecting ethylene oxide andpropylene oxide to ring-opening addition polymerization randomly to forman oxyalkylene random chain, changing the catalyst and subjectingethylene oxide to ring-opening addition polymerization in the presenceof an alkali metal catalyst to form an oxyethylene block chain; and is apolyoxyalkylene polyol having a hydroxyl value of from 5 to 56 mgKOH/g,a proportion of an initiator residue of at most 25 mass %, a proportionof the oxypropylene block chain of from 5 to 50 mass %, a totaloxyethylene group content of from 5 to 60 mass %, and a ratio of primaryhydroxyl groups among terminal hydroxyl groups of at least 60 mol %. 7.The method for producing a polymer dispersed polyol according to claim6, wherein in the formation of the oxyalkylene random chain, theproportion of ethylene oxide to propylene oxide to be subjected to thering-opening addition polymerization is within a range of from 3/97 to35/65 in a mass ratio.
 8. The method for producing a polymer dispersedpolyol according to claim 6, wherein the proportion of the oxyethyleneblock chain in the polyoxyalkylene polyol is from 3 to 40 mass %.
 9. Themethod for producing a polymer dispersed polyol according to claim 6,wherein the proportion of the oxyalkylene random chain in thepolyoxyalkylene polyol is from 5 to 90 mass %.
 10. The method forproducing a polymer dispersed polyol according to claim 6, wherein thedouble metal cyanide complex catalyst has a compound of the followingformula as at least part of organic ligands: R ¹ —C(CH ₃)₂(OR ⁰)_(n) OHwherein R¹ is a methyl group or an ethyl group, R⁰ is an ethylene groupor a group having a hydrogen atom of an ethylene group substituted witha methyl group or an ethyl group, and n is an integer of from 1 to 3.11. A method for producing a flexible polyurethane foam which comprisesreacting a polyol compound and a polyisocyanate compound in the presenceof a blowing agent and a catalyst, wherein as the polyol compound, apolyol mixture containing the polyoxyalkylene polyol obtained by theproduction method as defined in claim 1 is used.
 12. The method forproducing a flexible polyurethane foam according to claim 11, whereinthe degree of total unsaturation of the polyol compound is at most 0.05meq/g.
 13. The method for producing a flexible polyurethane foamaccording to claim 11, wherein a cell opener is added to produce theflexible polyurethane foam.
 14. The method for producing a flexiblepolyurethane foam according to claim 11, wherein the flexiblepolyurethane foam is produced in a sealed mold.
 15. A method forproducing a flexible polyurethane foam which comprises reacting a polyolcompound and a polyisocyanate compound in the presence of a blowingagent and a catalyst, wherein as the polyol compound, a polyol mixturecontaining the polymer dispersed polyol obtained by the productionmethod as defined in claim 6 is used.
 16. The method for producing aflexible polyurethane foam according to claim 15, wherein the degree oftotal unsaturation of the polyol compound is at most 0.05 meq/g.
 17. Themethod for producing a flexible polyurethane foam according to claim 15,wherein a cell opener is added to produce the flexible polyurethanefoam.
 18. The method for producing a flexible polyurethane foamaccording to claim 15, wherein the flexible polyurethane foam isproduced in a sealed mold.